Yes, everyone’s heard of Clausewitz.  Even those with no interest in studying war or strategy have probably come across his name in one context or another.  Yet there was a contemporary to Uncle Carl who similarly had a significant impact upon Western thinking about the conduct of warfare, Baron Antoine-Henri Jomini.  And it’s not too much of a stretch to say the two men battled for the military soul of the Western world that existed in the wake of Napoleon’s romp across Europe.

Jomini was born in Payene, Switzerland in 1779.  His father was the mayor there, descendant of an old Swiss family of Italian lineage.  Pushed by his family into a business education and career, Jomini always favored military topics and pursuits.  Accordingly, in 1798, having abandoned his work at a banking house in Paris, he found employment as a secretary for the Swiss Minister of War, a position that came with the rank of captain.

Jomini found himself beguiled by the exploits of Napoleon during the 1796-97 campaign in Italy which hastened an end to the War of the First Coalition.  This fascination complemented an appreciation for the campaigns of Frederick the Great from 1740 to 1778.  Eager to make a name for himself, and without having ever stepped onto an actual battlefield, Jomini was already hard at work on his first book on warfare and strategy.  He’d solve that little problem of experience by participating in the French 1805 campaign as a member of Marshal Michel Ney’s staff where he fought at the Battle of Ulm.  In return for his service Jomini was given a commission as a colonel in the French Army, and he published his Treatise on Major Military Operations that same year.

Jomini would continue to serve the French, enjoying the on-again-off-again patronage and interest of Marshal Ney, through the campaigns of the Fourth Coalition and, in 1806, he was attached to Napoleon’s staff in advance of the Prussian Campaign.  Jomini was with the Emperor at the Battles of Jena and Eylau, after which he was awarded the Legion of Honour.  Following the Peace of Tilsit in 1807, Jomini was made Ney’s Chief of Staff, which led to a falling out with his commander during the brutal Spanish Campaign.

The Russians reached out to Jomini, offering him a commission in the Army, but Napoleon intervened, convincing him to stay and granting him the rank of General of Brigade.  Still, for some years Jomini held commissions in both the French and Russian armies, a state of affairs that became awkward when Napoleon invaded Russia in 1812.  During the horrible French retreat from Moscow, Jomini abandoned his rear echelon posting and re-joined the army, fighting alongside Ney at the Battles of Lutzen and Bautzen.  He was recommended for promotion to the rank of Major General, but Napoleon’s Chief of Staff, Louis-Alexandre Berthier, greatly disliked Jomini and had him censured instead.  During the armistice which followed the disastrous campaign, Jomini crossed over into Russian service.

Jomini withdrew from the Russian Army when he couldn’t prevent the Allied violation of Swiss neutrality in 1814.  Yet he maintained enough standing within the Russian Army to find himself alongside Tsar Alexander when the latter entered Paris in 1815.  He nearly lost that standing while attempting to save the life of his former commander and patron, Marshal Ney.  After several years in retirement post-war, Jomini re-entered the Russian Army, retiring officially in 1829 after participating in the Russo-Turkish War of 1828-29.

Jomini died at Passy near Paris in 1869, indicating, perhaps, that the French held no hard feelings over his earlier desertion.  Still, in the time between his retirement and final breath, he advised the Russian Tsar throughout the Crimean War and kept busy writing treatises and essays. 

Jomini is best known for his work The Art of War, published in 1838, and the effect of his writings upon future generations of soldiers, strategists, and scholars.  He was a man of his times, an age called The Enlightenment, and wrote of war and strategy in a manner consistent with those times.  In short, Jomini believed in the reduction of the complexities of warfare into basic principles that, if strictly adhered to, would win any and every war.

His most important principle was one of mass, or more specifically, the application of the bulk of one’s army against a portion of the enemy force.  He saw this as being the key to victory by Frederick the Great on multiple occasions, as well as Napoleon in Italy.  Jomini was generally willing to risk weakness in other areas in order to achieve this overwhelming force at the point of decision.

Another key principle for Jomini was the use of interior lines, another factor he indicated as decisive for Napoleon during the Italian Campaign.  Jomini felt that the seizing of ground in a central position—meaning, often enough, surrounded by enemy forces on what he termed “concentric lines”—allowed for the previous principle to be used to best effect.  In other words, the surrounded force should use that position to lash out and engage piecemeal the divided enemy forces, defeating them in detail.

A further key Jomini principle of war is the use of Lines of Operation, by which he generally meant where an army fights, for what objective, and in what force.  This concept, introduced initially in his earliest work, was one Jomini would privately regret, yet his reputation was such, by that point, that he was forced to stand by it.  Yet toward the end of his life he’d come to feel the concept, as a principle, was simply too limiting.

Jomini saw the disciplined application of these principles as the key to victory in any war.  Yet there was always an exception that seemed to hover in the background of his writings, a caveat, of sorts, that makes sense when considering his research and experience revolved around two military geniuses, Frederick the Great and Napoleon Bonaparte.  Jomini expressed, often in guarded terms, that rare battlefield commanders would be able to overcome even the correct use of his principles of war, leaving readers to wonder ever after just how much he believed in his own writings.

That said, there is a stubbornness in his approach that becomes apparent throughout.  Not only in his adherence to a “lines of operation” approach that he no longer believed in, but in his insistence that changes in technology would never be able to compensate for or overcome the correct application of his universal principles of war.  This, of course, would be roundly mocked as the 19th Century drew to a close and the industrial revolution fueled the rapid development of ever more deadly weaponry. 

Following the embarrassing loss of a Jomini-inspired French Army to the Clausewitzian Prussians during the Franco-Prussian War of 1870, the works of Jomini lost much of their charm, though adherents would cling to his principles as stubbornly as the man himself.  Still, elements of his writings would live on in the influential works of Mahan and others, for unlike Clausewitz, Jomini included naval operations in his many essays, even addressing amphibious operations.

One of Jomini’s most inexplicable shortcomings is a view of warfare predominantly limited to state-on-state conflicts, mirroring a chief criticism of his Prussian contemporary.  Yet Clausewitz had never seen such a conflict up close and personal, while Jomini had participated in both Spanish and Russian Campaigns with the French.   He had first-hand knowledge of the difficulty involved with a traditional force seeking to bring an irregular one to battle.  He’d faced the ambushes, chased enemies which dissolved into the populace, and awakened to find whole companies missing or slaughtered around their campfires while he slept.  In the end, the only real space given over to discussion of such irregular warfare was to urge states not to get involved in such conflicts. 

Perhaps, then, Jomini’s most prescient observation and advice to future strategists lies in this most simple of principles.  There are countless nations that would have benefitted from his wisdom, however dated. 

Were he alive today, Jomini would likely be appalled at the ratio of irregular to traditional, state-on-state conflicts.  As well, inventions like tanks, combat aircraft, missiles, and nuclear weapons—to say nothing of tactics such as airborne operations and submarine warfare—would have caused him to seriously reconsider his beliefs in the universality of his principles of war.  Yet there is enough there in his writings to continue to affect modern warfare as lines of operation—despite his later regrets—continue to frame operational approaches to combat, and in turn gave birth to the strategic concept of “lines of effort”, which dominate military planning today.

Thus, while Jomini’s scientific, reductionist approach to strategy and war are largely seen as anachronistic remnants of a bygone era in military theory, seeds of truth survived the technological assault of the past century and continue to bear fruit 152 years after his death.  I think he’d chalk that up as success.

M. G. Haynes